Back support vest



FIG. 1 is a front perspective view of a back support vest showing my new design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a side elevational view, the left side is a mirror image thereof;

FIG. 6 is a top plan view thereof; and

FIG. 7 is a bottom plan view thereof.

The broken line showing of the person is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a back support vest, as shown and described. 